A British businessman and his wife have been formally arrested in Shanghai after being held in police detention for six weeks, it emerged yesterday.

Peter Humphrey, a well-known British corporate investigator and long-term China resident, who advised multinationals on fraud and business risk, and his wife Yu Yingzeng, an American citizen were detained by police on July 10 and formally arrested on Monday.

A source with knowledge of the investigation said that the arrests were believed to relate to alleged breaches of laws pertaining to the “purchase of personal information”. Mr Humphrey’s arrest has been linked to a high-profile investigation